21287648733316 has 81 divisors (see below), whose sum is σ = 44782798988151. Its totient is φ = 8828148243600.

The previous prime is 21287648733301. The next prime is 21287648733427. The reversal of 21287648733316 is 61333784678212.

The square root of 21287648733316 is 4613854.

It is a perfect power (a square), and thus also a powerful number.

It is an unprimeable number.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 2002407321 + ... + 2002417951.

Almost surely, 2^{21287648733316} is an apocalyptic number.

21287648733316 is the 4613854-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21287648733316

21287648733316 is an abundant number, since it is smaller than the sum of its proper divisors (23495150254835).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21287648733316 is an frugal number, since it uses more digits than its factorization.

21287648733316 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21342 (or 10671 counting only the distinct ones).

The product of its digits is 48771072, while the sum is 61.

The spelling of 21287648733316 in words is "twenty-one trillion, two hundred eighty-seven billion, six hundred forty-eight million, seven hundred thirty-three thousand, three hundred sixteen".